Abstract: An enhanced dead reckoning method determines the position of a participating vehicle. The participating vehicle is unable to receive signals from global positioning satellites. The position is calculated by way of observed time difference calculations and received signal strength indications. The position is also calculated by communicating with other participating vehicles or egress points.

Abstract: An enhanced mobile communication device, or on-board equipment, communicates according an enhanced ad-hoc mode of communication and an infrastructure mode of communication. A method switches between the enhanced ad-hoc mode of communications and the infrastructure mode of communications. The enhanced mobile communication device receives content and updates a geographic database. The enhanced mobile communication device reads the geographic database and transmits content. Data, such as location information from global positioning satellite signals, is collected by the enhanced mobile communication. On-board software of the enhanced mobile communication device communicates with the geographic database for computing routes, paths, and turn-by-turn direction.